Combine first 3 ingredients in a small bowl. Brush steak with half of hoisin mixture. Place steak on a broiler pan coated with cooking spray. Broil 6 minutes. Turn steak over; brush with remaining hoisin mixture. Broil 6 minutes or until desired degree of doneness. Place steak on a cutting board; let stand 5 minutes.
Combine cucumber and remaining ingredients in a bowl; toss to combine. Cut steak diagonally across grain into thin slices. Serve with cucumber salad.
Thaw 8 wonton wrappers, if frozen. Cut wrappers in half diagonally; brush tops of wrappers evenly with 2 teaspoons dark sesame oil. Combine 1/4 teaspoon Chinese five-spice powder and 1/8 teaspoon salt in a small bowl. Sprinkle wrappers evenly with five-spice powder mixture. Bake at 450° for 3 minutes or just until crisp.